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Fruit flies (Diptera: Tephritidae) are important quarantine pests that may cause even up to 100 per cent yield losses in cucurbits. Among them, Zeugodacus cucurbitae (Coquillett) and Dacus ciliatus Loew are the serious pests of cucurbits. Survey was conducted in Coimbatore (11°14'60.00"N; 77°18'60.00"E) and Dharmapuri (40°26.767'N; 79°58.933'W) districts of Tamil Nadu, India, during 2017-2018, in the fields of snake gourd, ridge gourd and bitter gourd. Approximately 10 infested fruits from each vegetable ecosystem were collected and placed in glass cages for 15-20 days. Emerged flies were identified by using the taxonomical keys and confirmed through molecular characterization. The overlapping abdominal tergites are the key character to distinguish the Bactrocera genus from Dacus. Further, the presence of median vittae, r-m cross vein on forewing pecten on the male's abdomen and black facets on the face are the identification characters for Z. cucurbitae. Whereas, D. ciliatus with two facial spots. The amplicon size of collected fruit flies was found to be 480 bp. The population of both Z. cucurbitae and D. ciliatus showed a significantly positive correlation with rainfall and relative humidity. Whereas, it was negative with respect to maximum temperature and sunshine hours in both the locations. [ABSTRACT FROM AUTHOR]

Field experiments on effectiveness of food baits in attracting fruit flies under cucurbit ecosystem were conducted at Coimbatore (11°1'6"N 76° 58'21"E and Dharmapuri (40° 26.767'N 79°58.9331'W) Tamil Nadu, India. The pulps of banana, papaya, sapota, snake gourd and pumpkin were used as base baits at different concentrations and food grade alcohol and vinegar were used as additives to endure attraction of fruit flies. The newly designed low cost fruit fly trap was used for keeping the food bait to trap the fruit flies. Among the fruit pulps tested, the banana and papaya attracted more number of fruit flies (116.25 and 96.25 flies/ trap/ day, respectively) at 30g concentration. Among the additives tested, 30g base bait added with alcohol was effective in attracting fruit flies at 3 ml concentration. The combination of 30 g of banana with 3 ml alcohol (157.5 flies/ trap/ day) and 30 g of papaya with 3ml of alcohol (153.25 flies/ trap /day) was found best food base baits for fruit flies under cucurbit ecosystem. The combination of 30 g of banana with 3 ml alcohol was highly economic and longevity (5-14 days) was more as compare to 30 g of papaya with 3ml of alcohol. The highest female to male ratio was recorded in ridge gourd in Coimbatore (0.78:1) and Dharmapuri (0.67:1). The F: M ratio in the trap catches revealed that parapheromones were completely male biased while the food bait based traps were attractive to both sexes. Thus, the indigenously designed low cost trap is highly economic, effective and target oriented. [ABSTRACT FROM AUTHOR]